Agency nurses cost the trust running Hillingdon's hospitals more than £600,000 more in three months than full-time staff would have, exclusive analysis reveals.

Hillingdon Hospitals NHS Foundation Trust spent £1,121,864 on “expensive” agency nurses in the second quarter of the 2014/15 financial year, according to a report published by the Royal College of Nursing (RCN).

Staff nurses would have cost £512,931 for the same number of hours work – a difference of £608,933.

However, to match the workload over the three months, the trust would have needed an extra 72 full-time nurses across its two hospitals.

It comes after the Care Quality Commission (CQC) published a report last week highlighting a shortage of nurses at the trust's hospitals, Hillingdon Hospital and Mount Vernon Hospital.

Because of this and other concerns, the CQC rated the trust as 'requires improvement' and issued it with two warning notices.

RCN's report found the trust spent more than 20 times more hiring agency nurses between July and September 2014 than during the same period two years earlier.

The figures – obtained through the Freedom of Information (FoI) Act – show that in the same quarter of 2012/13, the trust spent only £51,771 on agency nurses, meaning a 2,067% increase.

Mount Vernon Hospital, in Northwood

Speaking at the time of the report's publication, RCN's London regional director, Bernell Bussue, said: “London is facing a growing shortage of qualified nursing staff and today's figures show the cost which employers are having to bear to plug the gaps.

“The government needs to do much more to make London an attractive, affordable destination for nursing staff so that our hospital trusts can plan ahead and get enough permanent staff in place to provide high quality care at the level which patients expect.”

Across England, NHS trusts spent an average of £884,179 on agency nurses in the second quarter of 2014/15, according to RCN's Frontline First report.

This figure was just over twice that of the same period two years earlier, making Hillingdon's increase over this period almost exactly ten times the national average.

The report collated data from 168 of England's 231 trusts – those that responded to the authors' FoI requests.

The report said: “We wanted to get a sense of the scale of the problem. Our research reveals that the size of the increase in recent years is truly unprecedented.”

The Hillingdon trust pays nurses an annual salary of between £21,478 and £27,901, plus a 15% supplement, for 37.5 hours work per week, 48 weeks a year, accounting for at least 27 days holiday. This equates to around £16 an hour.

In comparison, the trust pays between £30 and £39 per hour for agency nurses.

In a statement, the trust said: “There is a national shortage of nursing staff, an issue which is particularly acute within London. In order to minimise the impact on patient care we have taken on agency staff whilst we increase our recruitment drive for full time nurses.”